| The strainbursts tests were carried out in different lithology rocks by the deep undergroundrockburst analogue testing machine. The acoustic emission (AE) Eigen-frequency spectrumcharacteristics of rock during the process of rockburst were obtained using two different types ofAE sensor sensitivity monitoring systems. Firstly, the experimental methods for strainbursts wereintroduced in detail, the strainbursts paths were explained using Hoek-Brown criterion; Secondly,the AE dominant frequency characteristics of rock in different lithology during the rockburstprocess were analysed using Fourier transform frequency spectrum analysis method under theinfluence of the sensor sensitivity. The influence of AE Eigen-frequency spectrum characteristicswas demonstrated using AE waveform voltage amplitude attenuation characteristics and dominantfrequency amplification characteristics when the AE sensors were placed in different positions.The relationship between microscopic crack features of fragments and AE Eigen-frequencyspectrum characteristics in key points during the rockburst process according to the crackpropagation type; the transgranular crack characteristics of fragments were especially analysed ineach key point, demonstrated the close relationship between the transgranular crack appearanceand continuous wave-low frequency-high energy characteristic of AE during rockburst phase. |
